Android onFinishInflate理解

在View中，有个onFinishInflate方法，当应用从XML加载该组件并用它构建界面之后调用的方法。所以有的同学习惯在该方法中做一些操作，比如通过findViewById获取对象，或者计算宽高等。

不过这有个坑

就是该方法，只有当自定义View，通过在XML中创建时才会调用。

如果是通过new方式创建，则不会执行该方法。

下面是测试的代码：

代码1

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}

<com.test.view.InflateView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Hello World!" />

InflateView生命周期输出

09-01 14:34:53.275 7608-7608/? D/InflateView: onFinishInflate
09-01 14:34:53.285 7608-7608/? D/InflateView: onAttachedToWindow
09-01 14:34:53.290 7608-7608/? D/InflateView: onMeasure
09-01 14:34:53.290 7608-7608/? D/InflateView: onMeasure
09-01 14:34:53.300 7608-7608/? D/InflateView: onMeasure
09-01 14:34:53.300 7608-7608/? D/InflateView: onMeasure
09-01 14:34:53.395 7608-7608/? D/InflateView: onMeasure
09-01 14:34:53.395 7608-7608/? D/InflateView: onMeasure
09-01 14:34:53.395 7608-7608/? D/InflateView: onLayout

可以看出，输出了onFinishInflate

代码2

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
InflateView view = new InflateView(this);
setContentView(view, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
}

InflateView生命周期输出

09-01 14:34:16.020 7608-7608/? D/InflateView: onAttachedToWindow
09-01 14:34:16.020 7608-7608/? D/InflateView: onMeasure
09-01 14:34:16.150 7608-7608/? D/InflateView: onLayout
09-01 14:34:16.180 7608-7608/? D/InflateView: onMeasure
09-01 14:34:16.180 7608-7608/? D/InflateView: onLayout

可以看出没有执行onFinishInflate